Endura

It is common practice in the North American region to define solar projects with an active power grid limit at the PCC and require the facility to be designed with the capability of operating anywhere within a power factor band defined by the utility. It's also common for inverters to be nominally rated in kVA. Prior to PVsyst v7.3, we were able to define a grid limit in MW, select Pnom as apparent power rating and to provide a PF setting for the inverters. With the update to V7.3, it appears that the selection of definition of Pnom is linked to the grid limit definition - so Pnom = apparent requires the grid limit in MVA and Pnom = active power requires the grid limit in MW. Is there a method to decouple this so simulations can be performed similar to pre-V7.3? The issue with having these linked is that I don't believe PVsyst is able to simulate the impacts of HV/MV transformers, cables, etc. on reactive power in the system, meaning simulation results will be incorrect for curtailment scenarios. It also makes simulating various PF setpoints tedious as it requires adjusting both the inverter PF setting and the grid limit MVA to attempt to limit MW semi-correctly. The original de-linked method worked well as reactive power could be managed in load flow software - with the required inverter setpoint to meet a PCC power factor defined in PVsyst so that the inverters were properly derated - and active power would be simulated accurately in PVsyst.

Thanks! That is what I expected, will proceed on this basis.

Does the Power Factor setting directly correlate to the Inverter Pnom limit or is it adjusted based on line losses & transformer losses as well? For greater clarity: Transformers and conductor systems (primarily long MV systems) change reactive power consumption within a PV plant so an inverter power factor setting would vary from the point of interconnection's Power Factor depending on the requirement (leading or lagging) and equipment/design of the PV plant. For performance modelling in PVsyst, should we be performing this load flow analysis externally and setting the Power Factor in PVsyst based on the requirement at the inverter? Or does PVsyst perform some adjustments to account for reactive power within the PV plant? For example, we have a plant with a long MV interconnection where the power factor at the grid point is 95% but the power factor at the inverter may be as low as 91% to deliver that PF to the grid. In this case, would the recommendation be to use 91% in PVsyst or 95%?